Conventional frequency dividers frequently have the disadvantage that they use many passive elements in a so called LO path (local oscillator path) which are area-intensive and thus have the disadvantage that they necessitate a large chip area. Such passive elements in the LO path may, for example, be RC networks (resistor/capacitor networks) in a polyphase filter and LC networks (inductor/capacitor networks). In particular, LC networks may cause undesired coupling effects. Thus, for example, a so-called LC tank in a divider may couple to an LC tank in an oscillator. These area-intensive members lead to high manufacturing costs for those conventional frequency dividers. Further, the undesired couplings lead to performance losses of those conventional frequency dividers.
US 2010/0097106 A1 shows a flexible non-integer frequency divider circuit using at least two mixers each.